Measuring waterThis page of the Water Science Picture Gallery contains images of how water information is collected by the U.S. Geological Survey (USGS). There's a tremendous amount of field work that has to be done to develop and maintain a nationwide system of water-data sampling. ![]() Surface-water sampling methods and equipment:![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Laboratory equipment and procedures:![]() |